The officers - now suspended without pay - are identified as Dustin Boone, Bailey Colletta, Randy Hays and Christopher Myers.

ST. LOUIS (KMOX) - Four St. Louis police officers have been indicted by a federal grand jury, accused of beating an undercover city officer during the Jason Stockley demonstrations.

It was a night of several arrests on the streets -- the St. Louis officers are accused beating one of their own, and then lying to the FBI about it.

The officers - now suspended without pay - are identified as Dustin Boone, Bailey Colletta, Randy Hays and Christopher Myers.

"I am deeply disappointed in the alleged actions of these individual officers; however, it is in no way reflective of the hard work and dedication exhibited by the men and women of our Department..." STATEMENT from @SLMPD Chief Hayden pic.twitter.com/q5Vf5bwzWa

L.H. is a 22-year veteran with the department, who was dressed in civilian clothes among the protesters to record and document any criminal activity he might see.

The arresting officers - Boone, Hays and Myers - are accused of violating the undercover officer's constitutional rights by using "unreasonable force," throwing him to the ground and kicking and striking him while he was not posing a threat to anyone.

Boone, Hays and Myers are also accused of destruction of evidence, mutilating the undercover officer's cell phone.

The fourth officer, Bailey Colletta, is accused of attempting to obstruct justice by making a series of "misleading assertions and false statements when she testified before the grand jury."

St. Louis Mayor Lyda Krewson released a statement saying, "We expect professionalism from every City employee. No exceptions. The charges brought against these officers today do not reflect the standards we hold ourselves to as public servants."

If convicted, the officers face the possibility of lengthy prison time, with maximums of 10 to 20 years for the various counts.

#BREAKING: 4 #STL officers indicted in U.S. District Court for Eastern District of MO on charges including suspicion of lying to FBI, use of excessive force related to assault of undercover STL officer during 2017 protest after Stockley court ruling. STATEMENT pic.twitter.com/Sm1Opo8hS9

Former SLMPD officer Jason Stockley was acquitted of a first-degree murder charge brought by the state in the shooting death of Anthony Lamar Smith in 2011.

Below is the entire news release from the U.S. Attorney’s Office:

WASHINGTON (News release) – A federal grand jury in St. Louis indicted four St. Louis Metropolitan Police Department (SLMPD) Police Officers for their conduct in connection with the arrest and assault of a fellow SLMPD police officer who was working undercover in downtown St. Louis during last year’s protests following the acquittal of a former SLMPD officer of a first-degree murder charge brought by the State of Missouri relating to the shooting death of a civilian.

“Law enforcement officers have an important duty to protect the members of the communities they serve and to enforce the law,” said Assistant Attorney General Eric Dreiband. “The Justice Department will continue to investigate and prosecute matters involving allegations of federal criminal civil rights violations.”

“These are serious charges and the vigorous enforcement of civil rights is essential to maintaining public trust in law enforcement,” said U.S. Attorney Jeff Jensen. “The SLMPD recognized the importance of this investigation and its leadership has cooperated at every turn. I continue to have great confidence in the brave and honorable men and women of the SLMPD, Chief John Hayden, and Public Safety Director Judge Jimmie Edwards.”

“I wish to commend SLMPD leadership for its cooperation and the support of this investigation. Law enforcement and the public have a common interest in identifying and holding accountable those who dishonor the badge,” said Special Agent in Charge Richard Quinn of the FBI St. Louis Division. “To that end, I am encouraging people to contact the FBI if you are a witness in this case.”

According to the indictment, in the days and weeks that followed the acquittal, which occurred on Sept. 15, 2017, there were protests throughout the City of St. Louis. In anticipation of protests, SLMPD activated its protest-response unit, the Civil Disobedience Team (CDT), detailing more than 200 SLMPD officers to CDT. SLMPD officers assigned to CDT were tasked with controlling the crowd as needed and arresting those individuals for whom there was probable cause to believe that they had committed crimes. Defendants Boone, Colletta, Hays, and Myers were all assigned to CDT and were working in their capacity as SLMPD officers during the protests. The listed victim in the indictment, L.H., a 22-year veteran SLMPD officer, was also working during the protests, but was doing so in an undercover capacity in order to record and document criminal activity so that other SLMPD officers could lawfully arrest individuals who were committing crimes.

Count One of the indictment charges defendants Boone, Hays, and Myers with willfully violating L.H.’s constitutional rights when they used unreasonable force on L.H., actions that resulted in bodily injury to L.H. and included the use of a dangerous weapon: shod feet and a riot baton. The indictment specifically alleges that Boone, Hays, and Myers threw L.H. to the ground and then kicked and struck L.H. while he was compliant and not posing a physical threat to anyone.

Count Two also charges defendants Boone, Hays, and Myers with conspiracy to obstruct justice for conspiring and agreeing to engage in misleading conduct toward witnesses to prevent information about their criminal conduct from reaching federal authorities.

Count Three of the indictment also charges defendant Myers with destruction of evidence for knowingly destroying and mutilating L.H’s cellular phone with the intent to impede, obstruct, and influence the investigation into the arrest and assault of L.H.

Count Four charges defendant Colletta with corruptly attempting to obstruct, influence, and impede federal grand jury proceedings by engaging in a series of misleading assertions and false statements when she testified before the grand jury.

Count One carries a maximum penalty of 10 years in prison. Counts Two, Three, and Four each carry maximum penalties of 20 years in prison. All four counts carry a maximum fine of $250,000.

An indictment is merely an accusation and the defendants are presumed innocent until and unless proven guilty.

This case is being investigated by the St. Louis Division of the FBI and is being prosecuted by Assistant United States Attorney Reginald Harris of the U.S. Attorney’s Office, Special Litigation Counsel Fara Gold, and Trial Attorney Emily Savner of the Department of Justice Civil Rights Division Criminal Section.